Skirted blower



Patented Dec. 10, 1940 UNITED STATES PATENT OFFICE 2,224,466 sxm'rnn BLOWER Clyde A. Baker, Stuart M. Dockerty, and Richard L. Hamilton, Corning, N. Y., assignors, by mesne Y assignments, to Owens-Corning Fiberzlas Corporation, Toledo, Ohio, a corporation of Delaware Application May 24, 1938, Serial No. 209,826

5 Claims. (01. 83-91) This invention relates to the production of to and in communication with a pressure header fibrous material and more particularly to the l3 which maybesupplied with steam, compressed structure of blowers by which such material may air or any suitable gas under pressure thru pipe be advantageously produced. H from a source, not shown. The two pressure Heretofore, it has been common practice to chambersinassembled position cooperate to form attenuate fine streams of plastic material to a rectangular body having a slot l5 extending fibrous form by subjecting them to the action therethru for a considerable distance along its of a series of jets of air or steam issuing at. longitudinal axis. A series of orifice openings high velocity from a pressure chamber. Both I6 are formed in the wall of each pressurechamorganic and inorganic fibres have been produced ber thruout the length of the slot and are so in this manner, great quantities of glass fibres inclined that they form an included angle of being produced with an electrically heated bushnot more than thirty degrees. An elongate strucing and steam blower as shown in the British patent to Triggs No. 428,720.

In the operation of a steam blower such as shown by Triggs large amounts of steam are consumed, usually in the neighborhood of six hundred pounds per hour whena pressure of one hundred forty pounds per square inch gauge pressure is used on the blower. When the bushing is run at a relatively low temperature so that the glass issuing therefrom is relatively-viscous long, substantially continuous fibres are produced which are especially suitable for manufacture into textile products. However, the output of a unit operated in this manner is relatively low, in the neighborhood of two pounds per hour and under such circumstances the amount of steam used constitutes a major item in the cost of the fibre produced. Y

The object of the present invention is an improved blower structure of high operating efliciency capable of attenuating fine streams of molten glass and similar plastic material to fibrous form.

This invention embodies among its features a pressure chamber so formed that a passage extends therethru and having a considerable number 'of openings for the production of a series of converging jets of gas adjacent said passage, and an elongate structure constituting a continuation of the aforementioned passage thru which the jets of gas pass after issuing from the pressure chamber. These and other features will be readily apparent from a study of the-particular apparatus hereafter more fully described and illustrated in the accompanying drawing in which:

Fig. 1 is a vertical transverse section thru the blower structure; and

Fig. 2 is a longitudinal section on line 2-2 of Fig. 1.

The blower of the present invention as illustrated in Figs. 1 and 2 may consist of a pair of elongate pressure chambers II and 12 attached the above slot and may be formed of a pair of angle irons l1 and I8 rigidly attached to the bottoms of the two pressure chambers. The edges of this slot may be closedwith light chanto angle irons l1 and I8.

In operation the blower structure is preferably positioned a short distance beneath the source of an electrically heated metallic bushing '20. When hot glass or other material is caused to fiow from the bushing tips, fluid pressure is applied to the header l3 and high velocity jets issue a short distance below their openings .and by. their aspirating action suck in a considerable body of air thru the top of the slot [5 "about the tips of the bushing 20. This air attains sufiicient velocity to draw the issuing glass away from the bushing and down into the slot of the bushing where a gradually increasing tractive force is applied increasing its velocity and at-' tenuating it to fibrous form.

Altho it is known that steam at one hundred forty pounds per square inch pressure will have a jet velocity of about 1700 feet per second when. exhausting thru an orifice toatmosphere and these in pre-existing blowers have been formed with a number of jets placed close together, it has been found that the glass fibres produced by such a blower operating at one hundred forty pounds per square inch pressure are drawn at second. This is believed due to the presence of the aspirated air drawn thru the top of the slot which forms a protecting sheath between the fibres and the high velocity steam jets. Tests have shown that the rate of fibre production exactly equals the velocity of the aspirated air thru the slot so the velocity of the steam jets is ture is provided which forms a continuation of nel members l9 screwed or otherwise attached of molten'material, here illustrated as the tips from the openings IS in approximately the di- I rection they are inclined. These jets converge the rate of only three hundred fifty feet per I transmitted to the fibres only as it is able to increase the velocity or the aspirated air.

In the present invention it has been found that the addition'of the angle irons I1 and I8 and channels l9 forming a continuation of the slot l5 increases the fibre drawing speed from three hundred fifty to eight hundred feet per second using the same pressure of steam on the blower. The reason for this phenomena is not fully understood, but it is believed that by increasing the length of the slot the issuing steam and aspirated air are confined in intimate contact and lateral expansion is prevented thus enabling the steam to expend a greater amount of its energy in raising the velocity of the aspirated air and the included fibres. It is believed that the length of the slot should be such that the entire mass of fibres, air and steam reach approximately a common velocity and in practice this will be found to vary with the .size of the slot, the number of jets and the blower pressure being used. Lengths of from two to twelve inches have been found desirable for different operating conditions in actual practice and may readily be determined for a given installation with a minimum of experimentation.

While the invention has been described in detail with respect to a particular blower construction, it is obvious that the principles involved are equally applicable to blowers of other construction an'd configuration including circular blowers designed to operate on a single stream of material. With these modifications in view the scope .of the invention is to be limited only by the terms of the appended claims.

We claim:

1. In a device for producing fibrous material, a blower structure comprising a housing having a pressure chamber therein and having a walled slot extending through, said housing, said slot comprising inlet and outlet openings, orifice openings in said housing walls along said slot for the issuance of jetsof fluid from said pressure chamber into said slot, said orifice openings being so positioned with respect to said slot as to cause a current of air to be drawn through said inlet opening by said jets, and an elongate open ended structure associated with said housing and constituting a smooth continuation of the slot therein, said structure being of from two to twelve inches in length and having a uniform cross section opening therethrough substantially equal to the outlet opening of said slot.

2. In a device for producing fibrous material, a blower structure comprising a housing having a pressure chamber therein and a walled passageway therethrough, orifice openings in the walls of said housing forming said passageway, said openings being inclined to the axis of the passageway, and a straight sided elongate hollow structure of uniform cross section attached to said housing and forming a smooth continuation of said passageway of from two to twelve inches in length, said structure being attached to the side of the housing toward which the orifice openings are directed.

3. In an apparatus for the production of fibrous material in combination a source of molten material, a blower positioned adjacent said source and having a passageway therethrough in alignment with said source, said blower having a plurality of oppositely disposed orifice openings therein so positioned as to direct convergent jets of gas into said passageway and toward the axis of said source, and an elongate structure attached to said blower and forming a continuation of the passageway therethrough and providing a restricted conduit of uniform cross section from two to twelve inches in length for the direction and confinement of the gases issuing from said orifice openings.

4. In an apparatus for the production of fibrous material in combination a source of molten material, a blower positioned adjacent said source comprising a pressure housing having a walled passageway therethrough in alignment with said source, said blower having a plurality of orifice openings in the walls of said passageway so positioned as to direct intersecting jets of gas through said passageway away from said source of molten material, and an open ended elongate structure attached to said blower and forming a restricted conduit of from two to twelve inches in length for the direction and confinement of the gases issuing from said orifice openings, said elongate structure forming a smooth continuation of 'said passageway and having a uniform cross sectional area throughout its length substantially equal to the cross sectional area of the passageway through said blower.

5. In an apparatus for the production of fibrous glass, a blower structure comprising a pressure housing having an open ended walled slot extending therethrough having entrance and discharge ends, orifice openings in the walls of the said pressure housing terminating in said slot and so positioned as to direct intersecting jets of gas through said slot toward the discharge end thereof and an open ended elongate structure attached to said blower and forming a restricted conduit in smooth continuation of said slot, said conduit having a uniform cross sectional area throughout its length substantially equal to the cross sectional area of said slot and a length of from two to twelve inches.

CLYDE A. BAIER. STUART M. DOCKERTY. RICHARD L. HAMILTON. 

